Honeywell Krom Schroder BCU 580 - Safety Time 2 T; Sa2; Flame Proving Period 2 T FS2

BCU 580 · Edition 11.15l 69
Parameters
10.3.6 Safety time 2 t
SA2
Parameter 96
During the safety time 2 t
SA2
, the flame on burner 2
(main flame) is ignited. It can be set to 2, 3, 5 or 10 s.
t
SA1
t
Z
04 06 07 08 02 03 00
t
t
FS1
t
SA2
t
FS2
5
13
V1
57 V4
1
14 V2
2
ϑ1
ϑ2
8
4
88
1
46
11
9
41
42
L1
1
43
2
17-18
Safety time 2 starts with the application of the ϑ2 sig-
nal (terminal 4). Valve V2 opens at the start of safety
time 2. The fuel supply to burner 2 is released so that
a flame can form. If no flame is detected at the end of
safety time 2, the valves are closed again. Depending
on parameter 08 (Burner 2 start-up attempts), the BCU
reacts either with an immediate safety shut-down with
fault lock-out (P08 = 1) or with one or two additional
start-up attempts (P08 = 2 or 3). The BCU will complete
a maximum of three start-up attempts.
Safety time 2 must be determined on the basis of cur-
rent national standards and regulations. The burner ap-
plication and the burner capacity are the main criteria
for this.
If the ϑ1 signal (terminal 1) drops out during safety
time 2, the valves will not be switched off until the end
of safety time 2.
10.3.7 Flame proving period 2 t
FS2
Parameter 97
Flame proving period 2 t
FS2
can be parameterized
to enable the flame on burner 2 to stabilize after the
elapse of safety time 2. Only when the flame proving
period has elapsed will the next program steps be initi-
ated by the BCU. The flame proving period can be set
between 0 and 20 s.
t
SA1
t
Z
04 06 07 08 02 03 00
t
t
FS1
t
SA2
t
FS2
5
13
V1
57 V4
1
14 V2
2
ϑ1
ϑ2
8
4
88
1
46
11
9
41
42
L1
1
43
2
17-18